We know Bhagat Singh as the revolutionary who challenged the British rule and sacrificed his life for the motherland. But very few of us know that he was also an independent thinker. He rejected the idea of god at a time when our country was riddled with superstitions and vocalizing anything against god was considered an utmost sin.

Back in 1930, just a year before he was executed, Bhagat Singh wrote an essay titled Why I am an Atheist. In this essay, he extensively talks about his beliefs and how he reached the conclusion that there exists no god. Written around 87 years ago, his thoughts and ideas still present a remarkable example of revolutionary thinking. 

Source: news18.com

Beginning with how the people around him came to ascribe his atheism to vanity and pride, he writes that he had never imagined that his belief, or the lack of it, would someday lead to such severe criticism.  

It is a matter of debate whether my lack of belief in the existence of an Omnipresent, Omniscient God is due to my arrogant pride and vanity. It never occurred to me that sometime in the future I would be involved in polemics of this kind. As a result of some discussions with my friends, I have realised that after having known me for a little time only, some of them have reached a kind of hasty conclusion about me that my atheism is my foolishness and that it is the outcome of my vanity.
Source: santabanta.com

It was not easy for him to deal with questions of faith after he had openly declared himself as an atheist. He writes how his friends believed that the fame that he had achieved after the Delhi bombing and Lahore Conspiracy had got to his head, leading him to reject the power of god. An allegation which he completely denies and offers a logical explanation as to why.

My friends say that after Delhi bombing and Lahore Conspiracy Case, I rocketed to fame and that this fact has turned my head. Let us discuss why this allegation is incorrect. I did not give up my belief in God after these incidents. I was an atheist even when I was an unknown figure. 
Source: grabhouse.com

Bhagat Singh then throws light to the days spent in National College where he grew doubtful about the existence of god, despite being a firm believer at that time.

In the Non-cooperation days, I got admission to the National College. During my stay in this college, I began thinking over all the religious polemics such that I grew sceptical about the existence of God. In spite of this fact I can say that my belief in God was firm and strong. I grew a beard and ‘Kais’ (long head of hair as a Sikh religious custom). In spite of this I could not convince myself of the efficacy of Sikh religion or any religion at all, for that matter. But I had an unswerving, unwavering belief in God.
Source: newsx.com

But the real change in his belief came when the entire responsibility of his party fell on his shoulders. He writes how he decided to read more and more in order to equip himself to defend his party against any kind of derision with the help of sound reasoning. 

It was then that his belief underwent a dynamic change and by the end of 1926, he had embraced atheism.

Till that time I was only a romantic revolutionary, just a follower of our leaders. Then came the time to shoulder the whole responsibility. For some time, a strong opposition put the very existence of the party into danger. Many leaders as well as many enthusiastic comrades began to uphold the party to ridicule. They jeered at us. It was a turning point in my revolutionary career. An incessant desire to study filled my heart. ‘Study more and more’, said I to myself so that I might be able to face the arguments of my opponents. ‘ My previous beliefs and convictions underwent a radical change. No more mysticism! No more blind faith! Now realism was our mode of thinking.  By the end of 1926, I was convinced that the belief in an Almighty, Supreme Being who created, guided and controlled the universe had no sound foundations. 
Source: wokaybye.blogspot.in

Making no bones about his opinion on the faith in god, Bhagat Singh openly proclaims that the origin of faith lies in a man's weakness to stand without any support in the face of obstacles. 

Beliefs make it easier to go through hardships, even make them pleasant. Man can find a strong support in God and an encouraging consolation in His Name. If you have no belief in Him, then there is no alternative but to depend upon yourself. It is not child’s play to stand firm on your feet amid storms and strong winds. 
Source: saharantimes.com

He goes on to describe the struggles a person faces when he discards the old and conventional beliefs of god and his power.

You go against popular feelings; you criticise a hero, a great man who is generally believed to be above criticism. What happens? No one will answer your arguments in a rational way; rather you will be considered vainglorious. Its reason is mental insipidity. Merciless criticism and independent thinking are the two necessary traits of revolutionary thinking. 
Source: sikh-history.com

But the most notable part of his essay comes when he asks two hard-hitting questions about the existence of god:

1. If, as you believe there is an Almighty, Omnipresent, Omniscient God, who created the earth or universe, please let me know, first of all, as to why he created this world? This world which is full of woe and grief, and countless miseries, where not even one person lives in peace.
Source: lahore.city-history.com

The revolutionary thinker ends his comprehensive essay with a well-defended argument and writes that people should rise above religious dogmas and tread on the path of reality, instead of finding comfort in a mystical entity. 

Society must fight against this belief in God as it fought against idol worship and other narrow conceptions of religion. In this way man will try to stand on his feet. Being realistic, he will have to throw his faith aside and face all adversaries with courage and valour.

You can read the full essay here